A flexible polyurethane foam is employed as e.g. a seat cushion for automobiles. In recent years, fogging that takes place on the surface of glass of automobiles, which is caused by a volatile organic compound (VOC) released from a flexible polyurethane foam, has been a problem, and reduction of the amount of a catalyst or a volatile organic compound such as a silicone compound, used for production of the flexible polyurethane foam, is desired.
With regard to the reduction of the catalyst, a method of producing a flexible polyurethane foam without using a catalyst (Patent Document 1), a method of using a reactive amine catalyst in which its structure is partially hydroxylated or aminated so as to react with an isocyanate, is, for example, known.
On the other hand, in the production of a flexible polyurethane foam, a foam stabilizer is usually used, and a silicone foam stabilizer is mainly used as the foam stabilizer. However, a reduction of a silicone foam stabilizer from a flexible polyurethane foam has hardly been tried so far.
As a polyurethane foam produced without using a foam stabilizer, an integral skin foam, a semirigid foam or the like is known. However, these polyurethane foams are employed for interior materials for automobiles other than seat cushions, and have different texture from the flexible polyurethane foam.
Further, it is known that by using, as an isocyanate compound, an isocyanate compound containing diphenylmethane diisocyanate (MDI) or polymethylene polyphenyl isocyanate (polymeric MDI) as the main component, a polyurethane foam can be produced without using a foam stabilizer. However, in a case where an isocyanate compound containing tolylene diisocyanate (TDI) as the main component, which is mainly used as a starting material of a flexible polyurethane foam, was used, the production of a flexible polyurethane foam itself was difficult without using a foam stabilizer.
On the other hand, a method of producing a flexible polyurethane foam by using a foam stabilizer and by using a polyoxyalkylene polyol produced by using a double metal cyanide complex catalyst is known (Patent Document 2).    Patent Document 1: JP-A-08-311149    Patent Document 2: JP-A-03-14812